Project Note renders malformed dbml

[jens-koster]

parse the below as a file, the db.dbml property corrupts the format by putting curly braces around the note.
Project DocDWH {
database_type: 'BigQuery'
Note: '''
# document related tables
markdown content here
'''
}

turns into the below in the dbml-property:
Project DocDWH {
database_type: 'BigQuery'
Note: {'''
# document related tables
markdown content here
'''}
}

this will not load again in pydbml due to the curly braces (or on dbdiagram.io)
I fixed it in note.py, it is just a question of removing the curly braces form the output in the dbml property. Didn't think to make a pull request before changing a lot more stuff in my fork, sorry about that!

[Vanderhoof]

Thanks for finding this! I'll fix this in the next version